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Ruby Puma Webserver

If you are using the Puma webserver for your Ruby app (Rails or otherwise), then you should take some additional steps due to the multi-threaded runtime being used. This applies to all threaded webservers for Ruby, not just Puma.

First, please refer to the documentation on Rails or Ruby appropriately, and then take these additional steps.

Dalli by default uses a single connection to each server. This works fine normally, but can become a bottleneck in a multi-threaded environment and limit performance. In this case, Dalli supports connection pooling, where multiple connections are created to MemCachier’s servers. To use this, start by adding the connection_pool gem to your Gemfile:

gem 'connection_pool'

Next, you’ll need to set the :pool_size configuration option when setting up Dalli. For example, in Rails your configuration would become:

config.cache_store = :mem_cache_store,
                    (ENV["MEMCACHIER_SERVERS"] || "").split(","),
                    {:username => ENV["MEMCACHIER_USERNAME"],
                     :password => ENV["MEMCACHIER_PASSWORD"],
                     :failover => true,
                     :socket_timeout => 1.5,
                     :socket_failure_delay => 0.2,
                     :down_retry_delay => 60,
                     :pool_size => 5

Where the number 5 should be chosen according to how many threads you will be running and the available concurrency on the machines running your webserver.